Do any wear/worn items 1st. If you want a totally-different handling dynamic, get a rear 17/18" replacement wheel, and go radials, you can re-use your front wheel. This will cost you about $1K if you but a new modded wheel from Kosman Engineering, and just walk-into a shop and buy some premium radial rubber, or it may be considerably cheaper if you buy a used wheel for the rear & wait for a sale price for radial tires, or order online. 110 width in-front is all you want to do w/the stock wheel.
Benefits? Assuming your steering head bearings aren't 'knackered,' and the fork has oil, and the swingarm pivot is torqued correctly, and your rear shocks aren't worn-out, you will see an end to front-end weave at higher speeds, easier turning and in L-R transitions, a big overall improvement compared to stock bias ply tires. My opinion is there is not another single improvement which you can make which changes the bike so-much for the better.
After that, stainless-steel brake lines in-front & HH pads, your calipers are fine for the type of use you are going to give the bike, but some people like to use the 6 piston (3 opposed-pair) calipers. I have a set and have never bothered mounting them because of the improvement in brake handling I got from the SS lines and HH pads.
Performance stuff is easy for bolt ons like a full exhaust, the new VooDoo looks like a reasonably-priced alternative to what-else is out there. Bolt-ons change the tone, but are generally considered to not improve power, save your $$ for a good full system. The Morley's Muscle carb kit and Dynojet Stage 7 (forget any DJet Stage 1 or 3) are what nearly-all the guys on here have. If you go to a full exhaust, you need to install the jet kit to make the bike make more power, after tuning.
Fork braces, frame braces, beefed-up swingarms, all can help handling they go from easy to hard and from $ to $$$ in that order.
For night riding, I would go to a 7" round halogen headlamp in either 35 watt or 55 watt. EMGO makes a relatively affordable steel side-bolt mount bucket, and you will need some 43 mm 'ears' to mount it to your forks, I suggest double-bolted ones w/rubber insulators for the fork tubes. Riding a bike equipped w/this improvement at night will make you wonder why you put-up w/the stocker's anemic output. If you look at ddmtuning.com, you can get a HID upgrade for not much more $ for that bucket, I suggest a 5000 or 6000 temp bulb (not an actual 'hotness' as you probably know, it refers to the color of the light output).
You are only limited by your bank account. I suggest reading a lot of posts on the mods of your choice by using the 'search' function on the forum, come-up w/a plan and budget, research your sources for sales and etc, and then have at-it. Planning will keep you from doing something like buying new bias-ply tires, and then deciding that you really should buy radials.
Good-luck.
unk:
